1. Field of the Invention
The present invention generally relates to steering systems for vehicles. More specifically, the present invention relates to power steering systems for snowmobiles.
2. Description of the Related Art
With some snowmobiles, a rider straddles a seat and grips a steering handlebar provided in front of the seat. The steering handlebar typically is disposed in a position at an upper end of a steering shaft. The steering shaft usually is located centrally in a transverse direction of the vehicle. A lower end of the steering shaft is connected through a linkage mechanism to a pair of right and left steering skis. The steering shaft is supported for free rotation within a steering column. The steering column can be supported on a frame of the vehicle body. A snowmobile typically includes a drive track mechanism under the seat for propelling the snowmobile.
Turning the steering handlebar, while the snowmobile is traveling, transmits a steering force to the steering skis through the steering shaft and the linkage mechanism. The steering skis turn in response to the steering force. The weight of the front part of the snowmobile acts on the steering skis. Additionally, the forces generated while traveling forward also act on the steering skis. Such forces can make it difficult to turn the handlebar of the snowmobile, especially if the snowmobile is large and is traveling at high speeds.
A power steering device reduces the amount of force that a user must provide to steer the snowmobile. A power steering device includes an electric motor to generate additional steering force. The power steering device has an input shaft on a first end facing the rear of the vehicle body and an output shaft on a second end facing the front of the vehicle body.
In a snowmobile, the rear part of the vehicle body is supported by the drive track mechanism located generally centrally in the transverse direction of the vehicle. The weight of the front part of the vehicle body preferably is balanced in the transverse direction of the vehicle. In some cases, a power steering device is positioned on one side of the vehicle body.
The input shaft of the power steering device typically is connected to the steering shaft through a universal joint located generally centrally in a transverse direction of the vehicle. The output shaft extends toward the front of the vehicle body, and its front end connects to a rack and pinion type steering system near a front portion of the vehicle.